The invention relates to torque-transmitting assemblies that can operate in more than one mode.
Torque-transmitting assemblies, such as clutch assemblies or brake assemblies, may be configured to operate in more than one mode. A prior clutch assembly, for example, includes a clutch pack, a piston actuator, and first and second independent control circuits in communication with first and second fluid chambers, respectively, for actuating the piston actuator. Under low gain mode, the first control circuit supplies fluid to the first fluid chamber to cause the piston actuator to apply a first axial force to the clutch pack. Under high gain mode, the first control circuit supplies fluid to the first fluid chamber and the second control circuit supplies fluid to the second fluid chamber to cause the piston actuator to apply a second axial force, greater than the first axial force, to the clutch pack.
With such a configuration, it may be difficult to achieve precise, repeatable control of the clutch assembly. Furthermore, because of the multiple pistons and control circuits, the clutch assembly is costly to manufacture.
The invention addresses the shortcomings of the prior art by providing a torque-transmitting assembly that can effectively and precisely operate in more than one mode. Furthermore, the assembly may be configured to operate using a single actuator.
Under the invention, a multi-mode torque-transmitting assembly includes a plate-supporting element having an axis, and a plate connected to the plate-supporting element such that the plate is axially movable with respect to the plate-supporting element between a first position and a second position in response to applied axial forces. Furthermore, the assembly includes a movement-inhibiting member in sufficient cooperation with the plate for selectively inhibiting axial movement of the plate. The movement-inhibiting member inhibits movement of the plate from the first position in response to a first axial force, and allows movement of the plate toward the second position in response to a second axial force greater than the first axial force, such that the assembly is operable in more than one mode.
Further under the invention, a method is provided for operating a multi-mode torque-transmitting assembly in multiple modes, wherein the torque-transmitting assembly includes a plate disposed between first and second additional plates, and the plate is axially movable between first and second positions in response to applied axial forces. The method includes the steps of applying a first axial force to the first additional plate such that the first additional plate engages the plate, while inhibiting axial movement of the plate so that the plate remains generally at the first position, thereby operating the assembly in a first mode; and applying a second axial force greater than the first axial force to the first additional plate such that the first additional plate causes the plate to move axially toward the second position in which the plate is engaged with the second additional plate, thereby operating the assembly in a second mode.